package com.hmdp.service.impl;

import com.hmdp.dto.Result;
import com.hmdp.entity.SeckillVoucher;
import com.hmdp.entity.VoucherOrder;
import com.hmdp.mapper.VoucherOrderMapper;
import com.hmdp.service.ISeckillVoucherService;
import com.hmdp.service.IVoucherOrderService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.utils.RedisIdWorker;
import com.hmdp.utils.UserHolder;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import java.time.LocalDateTime;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Service
public class VoucherOrderServiceImpl extends ServiceImpl<VoucherOrderMapper, VoucherOrder> implements IVoucherOrderService {

    @Resource
    private ISeckillVoucherService seckillVoucherService;

    @Resource
    private RedisIdWorker redisIdWorker;
    @Override
    public Result seckillVocher(Long voucherId) {

        //查询优惠券
        SeckillVoucher voucher = seckillVoucherService.getById(voucherId);

        //判断秒杀是否开始
        if(voucher.getBeginTime().isBefore(LocalDateTime.now())){
            //未开始
            return Result.fail("秒杀已经结束！");
        }
        //判断库存充足
        if (voucher.getStock()<1) {
            //不足
            return Result.fail("库存不足！");
        }

        /**
         * 一人一单
         */
        //查询id
        Long userId = UserHolder.getUser().getId();
        int  count= Math.toIntExact(query().eq("user_id", userId).eq("voucher_id", voucherId).count());
        //判断是否存在
        if(count>0){
            return Result.fail("用户已经购买过一次");
        }
        //扣减库存
        boolean  success= seckillVoucherService.update()
                .setSql("stock=stock-1")
                .eq("voucher_id",voucherId).gt("stock",0)//stock>0就可以
                .update();
        if(!success){
            //扣减失败
            return Result.fail("库存不足！");
        }
        //创建订单
        VoucherOrder voucherOrder = new VoucherOrder();
        //订单id
      long orderId=  redisIdWorker.nextId(("order"));
        voucherOrder.setId(orderId);
        //用户id
        voucherOrder.setUserId(userId);
        //代金券id
        voucherOrder.setVoucherId(voucherId);
        save(voucherOrder);
        return Result.ok(orderId);
    }
}
